Film strip processing device

ABSTRACT

A film strip processor having one or more processing tanks with a narrow neck portion through which the film is fed into and out of the tank, and a wider lower portion with a film guiding member that is oscillatable about an axis near the neck of the tank to provide intense agitation of the processing liquid.

United States Patent Inventor Appl. No.

Filed Patented Assignec Priority I Hendrik Jan Mensinga Riiswvijk, Netherlands 833,584

June 16, 1969 July 27, 1971 N.V. Optisehe lndustrie De Dude Delft, Van Miereveltaan Delft, Netherlands June 28, 1968 Netherlands FILM STRIP PROCESSING DEVICE 7 Claims, 3 Drawing Figs.

US. Cl 95/94, 95/89, 95/99, 118/425 Int. Cl. 003d 3/12 Field of Search 95/89, 90,

[56] References Cited UNITED STATES PATENTS 2,133,535 10/1938 Campolunghi 68/175 UX 2,354,225 7/1944 Stiffler 95/99 X 3,235,932 2/1966 Jones 68/175 X Primary Examiner-John M. Horan Assistant Examiner-Alan Mathews AttorneyArthur B. Colvin ABSTRACT: A film strip processor having one or more processing tanks with a narrow neck portion through which the film is fed into and out of the tank, and a wider lower portion with a film guiding member that is oscillatable about an axis near the neck of the tank to provide intense agitation of tlie processingliquid.

FILM STRIP PROCESSING DEVICE The invention relates to a device for processing film strips which comprises at least one tank for containing a processing solution, in which a film guiding member is mounted provided with guide rollers along which the film is continuously fed in the form of a loop.

Such devices are already well known in the art. They have, as a rule, a moderate processing rate. However, for many purposes it is essential to speed up as much as possible the developing process of exposed films. The time required for accomplishing development and fixation appears to be shorter the more elevated the temperature of the developing and fixing solution is. However, if this temperature is increased too much, fogging occurs on the film. It also appears that the processing time is dependent on the rate of agitation of the solution. By such agitation a continuous flow of fresh developing'agent is supplied to the film surface. So, development and fixation times can be minimized by using either strongly elevated temperatures, which might result in the appearance of fog on the film, or by applying a less elevated temperature so as to prevent fogging, combined with an intense agitation of the processing solution.

In one prior art film processor a high processing rate is achieved by guiding the film along a portion of the circum ference of a whirling drum, another. portion of which is suspended in the processing solution which has an increased temperature. As a. result of the fast rotation of the drum the solutioncarried around the circumference of the drum is applied against the relatively slowly passing film. Thus, the processing agent at the film surface will be more rapidly refreshed in comparison with the first mentioned devices in which more conventional agitation means, such as stirrers, are used.

A drawback of the rotating drum processor is the considerably greater loss of processing solution. due to evaporation and oxidation by air as compared with the conventional devices having processing tanks. Further, this device is unsuitable for use in airplanes because of the free liquid level. Finally, the evaporation of the processing solution can present other difficulties, e.g. when the solution contains poisonous agents as it is the case in some so-callcd monobath mixtures. These are solutions in which the film is simultaneously developed and fixed.

i It is an object of the invention to construct a device of the type initially referred to which provides an extremely effective refreshing actionof the processing agents at the film surface. Other objects are to diminish or eliminate the oxidation and the evaporation of the processing solution and. to prevent spilling of solution during use of the device in an aircraft or other moving vehicle.

According to the'inventionthe device comprises atank having a relatively narrow neck portion at its top through which the film strip is fed into and out of the tank, and awider lower portion for receiving the film loop, the device being further provided with driving means for giving that part of the film guidingmember which projects into the wider portion of the tank an oscillating movement about an axis positioned closely to the connection between the narrow neck portion and the wider lower portion.

An embodiment of the invention-will now be described by way of example and with reference to the accompanying drawing, in which:

FIG. I is a cross-sectional view of the device according to the invention;

FIG. 2.is a perspective view of the film guiding member, and

FIG, 3 is a detail of the film guiding member.

In FIG. I item I is the film developing tank and 2 is a washing tank. The tank I has mutually parallel front and rear walls at a distance slightly. exceeding the film width. It has a narrow neck portion 3 and a lower portion which progressively widens toward the urcuate bottom. Two guide rollers 4 and 4' are .Niiiimml inside the narrow neck 3 at the upper edge thereof.

The wider part of the tank I accommodates two guide rollers S and 5', a heating element 6 and a thermostat 7. To diminish loss of processing liquid by evaporation .a cooler 8 is mounted around the neck 3 and, additionally, the tank 1 is closed with a cover 9. This cover is integral with one part 10 of a film guiding member of which the other part 1 is pivotally connected to part 10 by means of a pin 12. Cover 9 is provided with two rollers 13 and 13 which are positioned over the guide rollers 4 and 4', respectively, when the tank is closed. From the fixed part 10 of the film guide member a shaft 15 projects about which a lever 14 is pivotable in a plane parallel to the front and rear walls of the tank I. At its lower end this lever 14 engages the movable part II of the film guide with a pin 23 sliding in a groove 24 at one side of the movable part I] (see FIG. 3), whereas the opposite end of the lever I4 is slipped through a slot 16 in the cover 9 (see FIG. 2). The lever 14 is reciprocated by an electric motor 17 through an eccentric 18, a system of bars 19 and 21, of which 21 is connected with the free end of the lever 14, and a lever 20 which is pivotable about an axis 22. In operation due to the oscillating movement of the lever 14, the pin 23 urges the movable part 10 of the film guide to swing in a reciprocating fashion.

If the device is to be used in an aircraft provisions must be made to prevent spilling of the solution through the slot I6. To that end, the lever 14 near its pivot has circular side edges whose center lies at the center of rotation 15 and these edges tightly cooperate with two vertical strips 25 and 25 to form an effective liquid sealing.

The film is threaded into the device by pulling it directly from the supply spool 27 next to the neck 3, along the rollers 28, 4, 4, 29 up to and including 33, and the sprocket 34 to the winding spool 35. .Then, by lowering the film guide member 10, 11 into the tank I the film is pulled down and thereby simultaneously stretched on the film guide. The film is threaded into the washing tank 2 in a similar way by closing this tank with a cover 36 provided with a number of fixed film guide members having guide rollers 37, 38, 39 and 40 at their free ends.

At the lower end of the film guide part I0 on both sides of the axis 12 two guide rollers 4] and 41' are mounted which are next-adjacent the rollers 5 and 5, respectively, when the film guide member is lowered into the tank I At its lower end the film guide part 11 is provided with a roller 42. This roller system keeps the film stretched on the film guide 10, 11 when the device is in operation.

Especially if the device has to be used in an aircraft it may be advantageous to reduce the dimensions of the device as much as possible. Therefore, the width of the developing tank I is so selected, that the film guide 10, 11 on either side moves closely along the front and rear walls, thus more or less dividing the tank into two compartments. In that case the oscillating movement of the film guide part II will produce strong variations in the height of the liquid level in the neck 3 on both sides of the film guide. In view of the'short developing time it will be most important, however, to expose all parts of the film during a same length of time vto the developing solution. Therefore, the portion 3 is locally widened at one side, thus forming a bypass 43 through'which the solution can flew back from one side-of the guiding member to the other.

To prevent the occurrence of air-bubbles on account of the strong agitation in the solution, partition screens 44 and 44 are mounted over the heating element 6 and the thermostat 7. In the embodiment shown of the-device the cooling water flowing through-the cooler 8 is used afterwards as washing liquid in the washing tank 2. The film'is threaded through the tank 2. in four loops and-finally passes a squeegee 45 when leaving the tank 2. Thesprocket 34 and the winding spool 35 are also driven by the electric motor 17 What I claim is:

1. Device for processing film strips, which comprises at leastone tank for containing a processing solution, in which a film which the film is continuously fed in the form of a loop,

characterized in that said processing tank has a relatively narrow neck portion at its top through which the film strip is fed into and out of the tank and a wider lower portion for receiving the film loop, the device further being provided with driving means for giving that part of the film guiding member which projects into the wider portion of the tank an Oscillating movement about an axis positioned closely to the connection between the narrow neck portion and the wider lower portion of the tank.

2. Device as set forth in claim 1, in which the film guiding member consists essentially of two parts, the fixed part which traverses the neck portion of the tank being provided with a cover member substantially closing said neck portion, and carrying at its free end the other part pivotally connected thereto.

3. Device as set forth in claim 2, in which the driving means comprises a lever pivotally supported by said fixed part of the film guiding member, the lever engaging at one end said pivotahle part of the film guiding member, and projecting at its other end through a slot in said cover.

4. Device as set forth in claim 3, in which said lever, in the region of its pivot, has circular side edges whose center lies at the levers center of rotation, said side edges engaging a pair of mutually parallel strips whereby a liquid-tight scaling is formed. v t

5. Device as set forth in claim I, wherein a cooler is provided around the narrow neck portion of the tank.

6. Device as set forth in claim 1, wherein said tank has mutually parallel front and rear walls at a mutual distance slightly greater than the width of the film, said lower part of the tank being of a shape progressively widening toward the bottom of the tank.

7. Device as set forth in claim 1, wherein said narrow neck portion of the tank is provided with a bypass channel so as to enable processing liquid to flow from one side of the film guiding member to the other. 

1. Device for processing film strips, which comprises at least one tank for containing a processing solution, in which a film guiding member is mounted provided with guide rollers along which the film is continuously fed in the form of a loop, characterized in that said processing tank has a relatively narrow neck portion at its top through which the film strip is fed into and out of the tank and a wider lower portion for receiving the film loop, the device further being provided with driving means for giving that part of the film guiding member which projects into the wider portion of the tank an oscillating movement about an axis positioned closely to the connection between the narrow neck portion and the wider lower portion of the tank.
 2. Device as set forth in claim 1, in which the film guiding member consists essentially of two parts, the fixed part which traverses the neck portion of the tank being provided with a cover member substantially closing said neck portion, and carrying at its free end the other part pivotally connected thereto.
 3. Device as set forth in claim 2, in which the driving means comprises a lever pivotally supported by said fixed part of the film guiding member, the lever engaging at one end said pivotable part of the film guiding member, and projecting at its other end through a slot in said cover.
 4. Device as set forth in claim 3, in which said lever, in the region of its pivot, has circular side edges whose center lies at the lever''s center of rotation, said side edges engaging a pair of mutually parallel strips whereby a liquid-tight sealing is formed.
 5. Device as set forth in claim 1, wherein a cooler is provided around the narrow neck portion of the tank.
 6. Device as set forth in claim 1, wherein said tank has mutually parallel front and rear walls at a mutual distance slightly greater than the width of the film, said lower part of the tank being of a shape progressively widening toward the bottom of the tank.
 7. Device as set forth in claim 1, wherein said narrow neck portion of the tank is provided with a bypass channel so as to enable processing liquid to flow from one side of the film guiding member to the other. 